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Check if an array is empty or exists
...ypeof array.length; // => "number"
Case Empty Array
Now since we tested all other possibilities, we're talking to an instance of Array. In order to make sure it's not empty, we ask about number of elements it's holding, and making sure it has more than zero elements.
firstArr...
What does an exclamation mark mean in the Swift language?
...
OK. So the docs talk about using ! when you know for sure it can be unwrapped. But you can run the code fine without it (a forth option for your list - implicit unwrapping) AND without checking first. You get back the value or nil if nil. But if you know for sure that ...
Why prefer two's complement over sign-and-magnitude for signed numbers?
... to 4 bits for size). In the two's complement way, they are 0010 and 1111. Now, let's say I want to add them.
Two's complement addition is very simple. You add numbers normally and any carry bit at the end is discarded. So they're added as follows:
0010
+ 1111
=10001
= 0001 (discard the carry)
...
Trim spaces from end of a NSString
...WhiteSpace((__bridge CFMutableStringRef) stringToTrim);
//stringToTrim is now "i needz trim"
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How does cookie based authentication work?
...y won't see your users' actual passwords.
Step 3: Client > User login
Now your user logs in. He/she provides their username/password and again, this is posted as a HTTP request to the server.
Step 4: Server > Validating login
The server looks up the username in the database, hashes the sup...
Cast List to List
...uit.Add(new Banana());
// Eek - it's a banana!
Apple apple = apples[0];
Now you can convert a List<Apple> to an IEnumerable<IFruit> in .NET 4 / C# 4 due to covariance, but if you want a List<IFruit> you'd have to create a new list. For example:
// In .NET 4, using the covarianc...
How to set a JVM TimeZone Properly
...perations be explicit about which time zone you want, and you will always know what you get independently of the JVM setting. Example:
System.out.println(ZonedDateTime.now(ZoneId.of("Asia/Dushanbe")));
Example output:
2018-10-11T14:59:16.742020+05:00[Asia/Dushanbe]
System.setProperty
F...
Using two values for one switch case statement
...
oh ok. That was easy. Didn't know I could do that
– Ankush
May 23 '13 at 6:14
18
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How to rethrow the same exception in SQL Server
...ce a reraise command, or the ability to catch only certain errors. But for now, use a workaround. Sorry.
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